21 lines
441 B
Python
21 lines
441 B
Python
import numpy as np
|
|
|
|
|
|
def extremum(x, y):
|
|
"""
|
|
Return extremum coordinates of quadratic fit
|
|
"""
|
|
pf = np.polyfit(x, y, 2, full=True)
|
|
p = pf[0]
|
|
res = pf[1][0]
|
|
f = np.poly1d(p)
|
|
if p[0] != 0:
|
|
x_ext = -p[1] / (2 * p[0])
|
|
y_ext = f(x_ext)
|
|
else:
|
|
x_ext = None
|
|
y_ext = None
|
|
x_fit = np.linspace(min(x), max(x), 100)
|
|
y_fit = f(x_fit)
|
|
return (x_ext, y_ext, x_fit, y_fit, res)
|